The present invention relates to the field of electric submersible pump assemblies and associated support equipment, and more particularly but not by way of limitation, to an electric submersible pump assembly having a tube seal section.
In oil wells and the like from which the production of fluids is desired, a variety of fluid lifting systems have been used to pump the fluids to surface holding and processing facilities. It is common to employ various types of downhole pumping systems to pump the subterranean formation fluids to surface collection equipment for transport to processing locations.
One such prior art pumping system is a submersible pumping assembly which is supported immersed in the fluids in the wellbore. The submersible pumping assembly having a pump and a motor to drive the pump to pressurize and pass the fluid through production tubing to a surface location. A typical electric submersible pump assembly (ESP) includes a submersible pump, an electric motor and a seal section interdisposed between the pump and the motor. The purpose of the seal section is to protect the motor from contamination as the wellbore fluid usually contains deleterious substances such as particulate solids and other debris from the formation. Prior art seal sections have not proved effective in preventing environmental contamination of the motor.
Thus, there is a need for a seal section capable of effectively preventing deleterious substances, such as particulate solids and other matter contained in formation fluids, from entering the motor where such contaminants can interfere with the efficient operation of the motor and can reduce the operational life of the motor.
The present invention provides an electric submersible pump assembly having a submersible pump, a submersible electric motor drivingly connected to the pump, and a seal assembly disposed between the submersible pump and the motor. The seal assembly is generally of tubular construction and provides fluid communication between the seal assembly cavity and the motor, such fluid communication being in a circuitous path effecting gravity segregation of contaminants, including particulate solids, in wellbore fluids. The seal assembly thereby controls and minimizes migration of particulate solids and the like into the body of the seal section and into the motor.